Why Certain Fruits Don't Mix

This fitness expert thinks you should follow the laws of food combining. Here's why.

Acid, sub-acid, sweet. If these aren’t terms you generally think of when picking out your pomegranates, papayas, and persimmons then you may need a lesson in how you pick and pair the fruits you eat.

Fruit typing is part of the overall concept of food combining, which follows the thinking that foods digest at different rates and ingesting an improper mix of foods can cause fermentation within the digestive system, slowing transit time and leading to bloating and possible bacterial imbalances.

The basic rules: Fruits should be consumed alone on an empty stomach; starches with cooked non-starchy vegetables; flesh proteins and dairy with cooked non-starchy vegetables; and nuts and seeds with raw vegetables.

“Proper food combining puts less effort and strain on our digestive system and faster, easier digestion increases the bioavailability of food,” says Mark Hendricks, group fitness manager at Toronto's Bay Street Club, who follows the protocol himself and advises clients to do the same. “We want our bodies to utilize the nutrients we ingest and this assists in the process and leads to healthy elimination as well.”

As a protocol, it can be particularly beneficial in helping to heal a digestive tract already compromised by an imbalance of flora, notes nutritionist Haylie Pomroy, author of the Fast Metabolism Diet and Fast Metabolism Diet Cookbook. But it’s a restrictive way to eat, nixing snack ideas like an apple with almond butter (a nutritionist favorite), all juice-smoothies that blend veggies with fruit, and arguably every unmodified restaurant meal.

Fruit typing, however, is an easy way to dip your toe into the idea and reap some of the benefits, Hendricks says. Here, his tips:

Separate acid from sweet...

Not all fruits play well together. Acid fruits like grapefruit and other citrus, pineapples, pomegranates, sour apples and plums, strawberries and tomatoes don’t pair well with sweet fruits like grapes, bananas, persimmon, figs, prunes, and dates.

...but buffer your acid.

Acidic fruits like grapefruit can be hard on the stomach. In that case, Hendricks tells clients to mix in a sub-acid fruit like blueberries. Subacid fruits—sweet apples, apricots, cherries, mangoes, nectarines, pears, papayas and berries—can mix with either acid or sweet fruits.

Enjoy melons on their own.

Melons like honeydew, cantaloupe, Crenshaw, and watermelon have a very high water content and digest even faster than the other fruits.

Skip the standard fruit salad.

It’s usually a digestion-slowing mix of melon, apple, pineapple, banana, and strawberry, says Hendricks. Instead, make a berry bowl using blueberries and raspberries.

Pick fiber-rich fruits pre-workout.

Melons are great for hydration but digest too quickly to sustain you, while the sugar in sweet fruits offers only short-lived energy. Instead choose a sub-acid fruit like a red apple or a nectarine with more density and fiber for staying power.